One-Piece Turbulence Insert

ABSTRACT

The invention relates to a one-piece turbulence insert for a heat exchanger ( 1 ), particularly for a radiator of a motor vehicle, comprising an essentially corrugated profile. The turbulence insert ( 24 ) has a number of sections ( 41 - 45 ) with corrugated profiles that extend in the same direction of the extension of the corrugations and which, perpendicular to the direction of the extension of the corrugations, are offset from one another. In order to enable a better thermodynamic efficiency, the turbulence insert ( 24 ) has a number of sections ( 27 - 32, 41, 45 ) with corrugated profiles extending in different directions of extension of the corrugations.

The invention relates to a one-piece turbulence insert for a heat exchanger, in particular an automotive cooler, having a substantially corrugated profile, the turbulence insert comprising a plurality of sections with corrugation profiles which propagate in the same direction of propagation and are offset to one another transversely to the direction of propagation.

Conventional turbulence inserts are produced using rolls. An oil/coolant cooler consisting of a plurality of plates arranged in parallel one above the other is known from German patent DE 197 09 601 C2. Each of the plates has on two opposed edges a respective inlet and outlet opening for a heat exchange medium. The plates form between them hollow chambers in which corrugated sheet-metal turbulence panels are provided to increase the heat transfer, each of the media used for heat transfer flowing through alternate chambers. The sheet-metal turbulence panels are subdivided into sections in which the corrugations are oriented differently. The sections are divided from one another by oblique separation cuts. The sheet-metal turbulence panels are rolled, the direction of rolling in adjacent sections being rotated through a predefinable angle with respect to the direction in the adjacent section. The respective inlet and outlet openings of each of the heat exchange media are so arranged in the sections that a flow from the inlet opening encounters greater resistance directly in the direction of the outlet opening than in a direction transverse thereto, so that a uniform distribution of flow in the associated hollow chamber is produced. The known sheet-metal turbulence panels are composed of a plurality of rolled parts in order to produce sections having different directions of propagation of the corrugations. Gate-like openings are produced transversely to the rolling direction, which openings have different widths in adjacent rows so that slot-like openings are formed in known fashion between adjacent gates, making possible not only a transverse flow through the gates but also a flow in a direction perpendicular thereto.

It is the object of the invention to provide a one-piece turbulence insert for a heat exchanger, in particular an automotive cooler, having a substantially corrugated profile, which turbulence insert comprises a plurality of sections having corrugation profiles that propagate in the same direction of propagation and are offset to one another transversely to the direction of propagation, which turbulence insert makes possible improved thermodynamic efficiency.

This object is achieved with a one-piece turbulence insert for a heat exchanger, in particular an automotive cooler, which has a substantially corrugated profile and comprising a plurality of sections with corrugation profiles which propagate in the same direction of propagation and are offset to one other transversely to the direction of propagation, in that the turbulence insert comprises a plurality of sections which have corrugation profiles propagating in different directions of propagation. The turbulence insert according to the invention makes possible a specified distribution of a medium within a flow channel and/or a specified stiffening of a heat exchanger under locally varying load states according to the local load tensors, and/or optimization of thermodynamic performance by a suitably formed rib structure in some or all of the flow channels of a heat exchanger. The turbulence insert according to the invention is formed either as a whole or in segments, using a combined punching and deep-drawing process. The structure of the turbulence insert may also be in the form of a closed structure. In that case the punching process may be omitted.

A preferred embodiment of the turbulence insert is characterized in that the turbulence insert comprises a plurality of rectangular sections having corrugation profiles propagating in different directions of propagation. Flow through a flow channel in different directions is thereby made possible.

A further preferred embodiment of the turbulence insert is characterized in that the turbulence insert is formed from a substantially rectangular plate which comprises a central portion having a plurality of sections with corrugation profiles propagating transversely to the longitudinal direction of the plate, and two outer portions having a plurality of sections with corrugation profiles propagating at an angle from 0 to 90 degrees with respect to a longitudinal side of the plate. The outer portions are preferably arranged at a medium inlet and a medium outlet. For this reason the outer portions are also referred to as inlet and outlet portions. The flow at the inlet and the outlet preferably takes place transversely to the longitudinal direction of the plate. The inventive configuration of the inlet and outlet portions makes possible a flow between the inlet and outlet portions and the central portion which is optimized fluidically and thermally.

A further preferred embodiment of the turbulence insert is characterized in that the corrugation profiles in the sections of the outer portions arranged closer to the central portion propagate at a larger angle with respect to a longitudinal side of the plate than in the sections arranged further towards the outside. At the ends of the plate the corrugation profiles are preferably disposed at an angle from 50 to 80 degrees to the associated longitudinal side of the plate. In the vicinity of the central portion the corrugation profiles are preferably disposed at an angle from 10 to 40 degrees to the associated longitudinal side of the plate. This makes possible a gentle deflection of the flow from the longitudinal side of the plate towards the central portion.

A further preferred embodiment of the turbulence insert is characterized in that the angle with respect to a longitudinal side of the plate at which the corrugation profiles propagate in the outer portions of the plate decreases from the central portion towards the outside. This makes possible a gentle deflection of the flow from the longitudinal side of the plate towards the central portion.

A further preferred embodiment of the turbulence insert is characterized in that the turbulence insert is formed by a substantially rectangular plate which comprises a central portion having a plurality of sections with corrugation profiles which propagate transversely to the longitudinal direction of the plate, and two outer portions having a plurality of sections with corrugation profiles which propagate in the longitudinal direction of the plate. Gate-like openings which have different widths in adjacent portions are formed transversely to the longitudinal orientation of the corrugations, so that slot-like openings are produced between respective adjacent gates, making possible a flow which passes not only transversely through the gates but also in a direction perpendicular thereto.

A further preferred embodiment of the turbulence insert is characterized in that deflection sections are formed between the corrugated profile sections which propagate transversely and longitudinally. The flow is deflected through 90 degrees in the deflection sections.

A further preferred embodiment of the turbulence insert is characterized in that the deflection sections are arranged diagonally in the outer portions of the plate. The formation of dead-water zones is thereby reduced.

A further preferred embodiment of the turbulence insert is characterized in that the direction of propagation of the corrugations changes by 90 degrees in the deflection sections. The transition zone preferably has a rounded configuration.

In an automotive cooler, in particular an exhaust gas cooler of a commercial vehicle, the object specified above is achieved by the use of a turbulence insert as described hereinbefore.

Further advantages, features and details of the invention are apparent from the following description, in which diffferent embodiments are described in detail with reference to the drawings. Each of the features mentioned in the claims and in the description can be essential to the invention in isolation or in any combination. In the drawings:

FIG. 1 is a perspective view of an exhaust gas cooler of a commercial vehicle;

FIG. 2 is a perspective view of a turbulence insert according to a first embodiment;

FIG. 3 is a view of a section through the turbulence insert of FIG. 1 at half-height;

FIG. 4 is a top view of a turbulence insert according to a further embodiment, and

FIG. 5 is a view of a section through the turbulence insert of FIG. 4 at half-height.

FIG. 1 shows an exhaust gas cooler 1 of a commercial vehicle in a perspective view. The exhaust gas cooler 1 comprises a cooler housing 2 which has substantially the shape of an elongated cuboid. A coolant inlet connecting piece 3 and a coolant outlet connecting piece 4 are arranged on the upper face of the cooler housing 2. An exhaust gas inlet connecting piece 6 and an exhaust gas outlet connecting piece 7 are mounted on the end faces of the cooler housing 2. Exhaust gas can enter the cooler housing 2 through the exhaust gas inlet connecting piece 6 and is directed through a multiplicity of exhaust gas flow channels in the longitudinal direction of the cooler housing 2 to the exhaust gas outlet connecting piece 7. A substantially flat oblong coolant flow channel is arranged between each two substantially flat oblong exhaust gas flow channels. The disposition of the coolant flow channels in the cooler housing 2 is indicated by arrows 11 to 14. The coolant serves to cool the exhaust gas of the commercial vehicle which is directed through the cooler housing 2. The zone in which the flow takes place substantially in the longitudinal direction through the cooler housing 2 is also referred to as the central zone. The central zone is delimited towards the outside by an inlet zone and an outlet zone. In the inlet zone the flow must be deflected through 90 degrees, as indicated by the arrows 18. Similarly, in the outlet zone the flow must be deflected through 90 degrees, as indicated by the arrows 19. In FIG. 1 there is an increased danger that dead-water zones will form at two locations 22. Turbulence inserts are arranged in the flow channels in order, inter alia, to prevent the formation of such dead-water zones.

FIGS. 2 and 3 show a first embodiment of a turbulence insert 24 according to the invention in perspective and sectional views respectively. The turbulence insert 24 is formed in one piece from a rectangular plate in a piece of aluminum sheet. A substantially triangular inlet portion 25 is formed at one end of the turbulence insert 24. Six rectangular corrugated profile sections 27 to 32 are arranged side-by-side in the inlet portion 25. The corrugated profile sections 34 to 38 are corrugated in the longitudinal direction of the turbulence insert 24. The corrugated profile section 27 comprises five corrugation crests 34 to 38 which are arranged equidistantly from one another. The corrugation profile section 28 comprises five corrugation crests which are offset with respect to the corrugation crests of the corrugated profile section 27. The corrugated profile section 29 comprises three, corrugation crests which are offset with respect to the corrugation crests of the corrugated profile section 28. The corrugated profile section 30 comprises three corrugation crests which are offset with respect to the corrugation crests of the corrugated profile section 29. The corrugated profile sections 31 and 32 each comprise one corrugation crest which is offset with respect to the adjacent corrugation crest or crests. The corrugation profiles of the corrugated profile sections 27 to 32 are open at both sides, so that a flow can pass through them transversely to the longitudinal direction of the plate.

A central portion 40, in which a multiplicity of rectangular corrugated profile sections 41 to 45 are arranged transversely to the longitudinal direction of the plate, extends in the middle of the plate. The corrugation profiles of the corrugated profile sections 41 to 45 propagate transversely to the longitudinal direction of the plate and are offset to one another. A cut line 47 indicates that the central portion 40 is significantly larger than is represented in FIGS. 2 and 3. The central portion 40 has substantially the shape of an equilateral trapezium.

A substantially diagonally-disposed deflection portion 50 is provided between the inlet portion 25 and the central portion 40. The deflection portion 50 comprises a multiplicity of deflection sections 52 to 55 in which the flow is deflected through 90 degrees from the inlet portion 25 to the central portion 40.

An outlet portion 60, which is configured symmetrically to the inlet portion 25, is arranged at the end of the turbulence insert 24 opposite the inlet portion 25. A deflection portion 65, which comprises a multiplicity of deflection sections 66 to 68 and is configured symmetrically to the deflection portion 50, is provided between the outlet portion 60 and the central portion 40. The associated axis of symmetry is disposed transversely through the centre of the turbulence insert 24.

FIGS. 4 and 5 show a turbulence insert 70 in two different views. The turbulence insert 70 is formed from a piece of aluminum sheet and is rectangular in shape. The turbulence insert 70 is subdivided into an inlet portion 71, a central portion 72 and an outlet portion 73. The inlet portion 71 comprises a multiplicity of corrugated profile sections 75 to 80 which are rectangular in shape. The corrugated profile sections 75 to 80 each include two corrugation crests arranged at a distance 82 from one another. The corrugations in the corrugated profile section 75 propagate at an angle of approximately 65 degrees to a longitudinal side of the turbulence insert 70. The corrugations of the corrugated profile section 80 propagate at an angle of approximately 30 degrees to the associated longitudinal side of the turbulence insert 70. Between them the angle of the direction of propagation of the corrugations with respect to the longitudinal side of the turbulence insert 70 decreases from the outside towards the central portion 72.

The central portion 72 comprises three corrugated profile sections 84 to 86 which are rectangular in shape. The corrugations in the corrugated profile sections 84 to 86 propagate transversely with respect to the longitudinal direction of the plate. The corrugation crests of the corrugated profile sections 84 to 86 are offset to one another. The turbulence insert 70 has a symmetrical configuration in relation to an axis of symmetry disposed transversely through the centre of the turbulence insert 70. 

1. A one-piece turbulence insert for a heat exchanger, in particular an automotive cooler, which has a substantially corrugated profile, the turbulence insert comprising a plurality of sections with corrugation profiles which propagate in the same direction of propagation and are offset to one another transversely to the direction of propagation, wherein the turbulence insert comprises a plurality of sections which have corrugation profiles propagating in different directions of propagation.
 2. The turbulence insert as claimed in claim 1, wherein the turbulence insert comprises a plurality of rectangular sections having corrugation profiles propagating in different directions of propagation.
 3. The turbulence insert as claimed in claim 2, wherein the turbulence insert is formed from a substantially rectangular plate which comprises a central portion having a plurality of sections with corrugation profiles propagating transversely to the longitudinal direction of the plate, and two outer portions having a plurality of sections with corrugation profiles propagating at an angle from 0 to 90 degrees with respect to a longitudinal side of the plate.
 4. The turbulence insert as claimed in claim 3, wherein the corrugation profiles in the sections of the outer portions arranged closer to the central portion propagate at a larger angle with respect to a longitudinal side of the plate than in the sections arranged further towards the outside.
 5. The turbulence insert as claimed in claim 4, wherein the angle with respect to a longitudinal side of the plate at which the corrugation profiles propagate in the outer portions of the plate decreases from the central portion towards the outside.
 6. The turbulence insert as claimed in claim 1, wherein the turbulence insert is formed by a substantially rectangular plate which comprises a central portion having a plurality of sections with corrugation profiles which propagate transversely to the longitudinal direction of the plate, and two outer portions having a plurality of sections with corrugation profiles which propagate in the longitudinal direction of the plate.
 7. The turbulence insert as claimed in claim 6, wherein deflection sections are formed between the corrugated profile sections which propagate transversely and longitudinally.
 8. The turbulence insert as claimed in claim 7, wherein the deflection sections are arranged diagonally in the outer portions of the plate.
 9. The turbulence insert as claimed in claim 8, wherein the direction of propagation of the corrugations changes in the deflection sections by 70 to 110 degrees, preferably by 85 to 95 degrees, especially preferably by 90 degrees.
 10. The turbulence insert as claimed in claim 1, wherein a fluid can flow successively through the sections which have corrugation profiles propagating in different directions of propagation.
 11. The turbulence insert as claimed in claim 1, wherein the direction of propagation of the corrugations within a section forms an acute angle with respect to one, in particular to all, boundaries of the section.
 12. The turbulence insert as claimed in claim 11, wherein the acute angle changes its sign from a first section to an adjacent second section.
 13. The turbulence insert as claimed in claim 1, wherein at least one corrugation profile extends across a boundary of two adjacent sections and, in particular, has curved flanks.
 14. An automotive heat exchanger, in particular a charge air cooler, an exhaust gas cooler or a coolant evaporator or condenser, having a turbulence insert as claimed in claim
 1. 15. The automotive cooler as claimed in claim 1, wherein the turbulence insert is fixed in a flow channel in a form-fitting manner.
 16. The automotive cooler as claimed in claim 1, wherein the turbulence insert is soldered, welded or bonded in a flow channel.
 17. The automotive cooler as claimed in claim 1, wherein the flow channel is formed by a tube or by two plates placed or stacked upon one another, or between two tubes. 